'I don't expect to ever return': Joyce investigation called off

Barnaby Joyce says an investigation into whether he breached the ministerial code had no bearing on his decision to quit as Nationals leader and deputy prime minister.

The investigation was called off when Mr Joyce stood down last Friday.

It was revealed yesterday Malcolm Turnbull asked his department boss, Martin Parkinson, to look into the affair nine days after the storm erupted, and six days after the Prime Minister’s extraordinary attack on Mr Joyce’s “shocking error of judgement”.

The former deputy prime minister has now found a home on the government's back bench. (AAP) ()

A second investigation is examining Mr Joyce’s taxpayer funded travel, with former media advisor and now pregnant partner Vikki Campion, and whether any ministerial guidelines were breached.

“No it did not, not at all,” Mr Joyce said when asked if the investigation by Dr Parkinson pressured him to resign.

In an early morning email to Dr Parkinson, Mr Turnbull asked him to “provide me with advice relating to (Mr Joyce)”